In an examination, Mandar scored 80 marks in Mathematics, 95 marks in Science, 74 marks in Social Studies, 65 marks in English and 72 marks in Hindi. If all the papers were out of 100, what is Mandar's overall percentage in the examination ?

Shilpa can complete a piece of work in 15 days and Shamita can complete the same piece of work in 24 days. In approximately, how many days can Shilpa and Shamita together complete the same piece of work ?

Supriya's monthly income is twice Deepa's monthly income. The ratio of the monthly income of Deepa and Sandhya is 7 : 3 respectively and their average monthly income is Rs 25,000. What is Supriya's monthly income ?

Vinita invested a certain amount at the rate of 8 p.c.p.a. for 5 years and obtained a simple interest of 3,800. Had she invested the same amount at the same rate of interest for 2 years, how much amount would she have obtained as compound interest at the end of 2 years ?